Method and apparatus for a catalytic firebox reactor

Abstract

A catalytic firebox reactor employing an exothermic catalytic reaction channel and multiple cooling conduits for creating a partially reacted fuel/oxidant mixture. An oxidation catalyst is deposited on the walls forming the boundary between the multiple cooling conduits and the exothermic catalytic reaction channel, on the side of the walls facing the exothermic catalytic reaction channel. This configuration allows the oxidation catalyst to be backside cooled by any fluid passing through the cooling conduits. The heat of reaction is added to both the fluid in the exothermic catalytic reaction channel and the fluid passing through the cooling conduits. After discharge of the fluids from the exothermic catalytic reaction channel, the fluids mix to create a single combined flow. A further innovation in the reactor incorporates geometric changes in the exothermic catalytic reaction channel to provide streamwise variation of the velocity of the fluids in the reactor.

What is claimed is:  
     
       1. A catalytic firebox reactor comprising: 
       a casing having an inlet and an outlet, and an interior surface and an exterior surface, the casing interior surface defining an interior chamber;  
       at least two conduits, each conduit having an inlet and an outlet, and an interior surface and an exterior surface, the conduits retained within the interior chamber, the conduit exterior surfaces and the casing interior surface forming an exothermic catalytic reaction channel having an exit, the exothermic catalytic reaction channel exit and the conduit outlets proximately located such that a first fluid upon exiting the conduit outlet is in contact with a second fluid that has exited the exothermic catalytic reaction channel, and  
       an oxidation catalyst deposited within the exothermic catalytic reaction channel on at least a portion of at least one of the conduit exterior surfaces, the oxidation catalyst being backside cooled from the conduit interior surface by the second fluid.  
     
     
       2. A catalytic firebox reactor of claim  1  wherein the conduits are retained by a retainer, the conduits passing through the retainer and connected thereto and the retainer connected to said casing, the retainer having passages therethrough. 
     
     
       3. A catalytic firebox of claim  1  wherein the conduits are retained by connecting the conduits to each other forming a bundle, the bundle connected to said casing, wherein at least one of any two adjacent conduits has at least one first expanded cross-section, the first expanded cross-section being sufficient to create the exothermic catalytic reaction channel. 
     
     
       4. A catalytic firebox of claim  3  wherein the conduit with the first expanded cross-section has a second expanded cross-section, the first expanded cross-section being located near the conduit inlet and the second expanded cross-section being located near the conduit outlet. 
     
     
       5. A catalytic firebox reactor of claim  1  wherein the conduits are retained by a single attachment, whereby the conduits are free to expand axially. 
     
     
       6. A catalytic firebox reactor of claim  5  wherein the single attachment is a retainer, the retainer being open to the passage of fluid, the retainer being attached to said casing. 
     
     
       7. A catalytic firebox reactor of claim  5  wherein said single attachment location is near the upstream end of said conduits. 
     
     
       8. A catalytic firebox reactor comprising: 
       a casing having an inlet and an outlet, and an interior surface and an exterior surface, the casing interior surface defining an interior chamber;  
       at least two conduits, each conduit having an inlet and an outlet, and an interior surface and an exterior surface, the conduits retained within the interior chamber, the conduit exterior surfaces and the casing interior surface forming an exothermic catalytic reaction channel having an exit, the exothermic catalytic reaction channel exit and the conduit outlets proximately located such that a first fluid upon exiting the conduit outlet is in contact with a second fluid that has exited the exothermic catalytic reaction channel, wherein the conduits are retained within the casing by a securing structure comprising a first retainer that is open to the passage of fluid connected to said casing upstream of the conduit inlets, and a second retainer that is open to the passage of fluid connected to said casing downstream of the conduit outlets wherein at least one of any two adjacent conduits has at least one locally expanded cross-section whereby when aggregated with the adjacent conduit creates the exothermic catalytic reaction channel; and  
       an oxidation catalyst deposited within the exothermic catalytic reaction channel on at least a portion of at least one of the conduit exterior surfaces.  
     
     
       9. A catalytic firebox of claim  8  wherein there are at least two locally expanded cross-sections, a first cross-section located near the conduit inlet and a second cross-section located near the conduit outlet. 
     
     
       10. A catalytic firebox reactor comprising: 
       a casing having an inlet and an outlet, and an interior surface and an exterior surface, the casing interior surface defining an interior chamber;  
       at least two conduits, each having an inlet, an outlet, an interior surface and an exterior surface, the conduits retained within the interior chamber, the conduit exterior surfaces and the casing interior surface forming an exothermic catalytic reaction channel having an exit, the exothermic catalytic reaction channel exit and the conduit outlets proximately located such that a first fluid upon exiting the conduit outlet is in contact with a second fluid that has exited the exothermic catalytic reaction channel, wherein the conduits are retained by a single attachment, whereby the conduits are free to expand axially, wherein at least one of any two adjacent conduits has at least one locally expanded cross-section such that when aggregated with adjacent conduits the conduits are laterally positioned within the interior chamber, and the securing means is a bundle created by connecting adjacent conduits at a single attachment location and connecting the bundle to said casing; and  
       an oxidation catalyst deposited within the exothermic catalytic reaction channel on at least a portion of at least one of the conduit exterior surfaces.  
     
     
       11. A catalytic firebox reactor comprising: 
       a casing having an inlet and an outlet and defining an interior chamber;  
       a first retainer positioned in the interior chamber connected to said casing, the first retainer being open to the passage of fluid;  
       a second retainer positioned within said interior chamber downstream of the first retainer connected to said casing, the second retainer being open to the passage of fluid;  
       at least two conduits, each conduit having an inlet and an outlet and an interior surface and an exterior surface, the conduits positioned longitudinally within the interior chamber, the conduits connected to the retainers, the conduit exterior surfaces and the casing interior surface forming an exothermic catalytic reaction channel having an exit, the exothermic catalytic reaction channel exit and the conduit outlets proximately located such that a first fluid upon exiting the conduit outlet is in contact with a second fluid that has exited the exothermic catalytic channel; and  
       an oxidation catalyst deposited within the exothermic catalytic reaction channel on at least a portion of at least one of the conduit exterior surfaces, the oxidation catalyst being backside cooled from the conduit interior surface by the second fluid.  
     
     
       12. A catalytic firebox reactor comprising: 
       a casing having an inlet and an outlet and defining an interior chamber;  
       at least two conduits with a nominal cross-section, each conduit having an inlet and an outlet and an interior surface and an exterior surface, the conduits positioned within the interior chamber, each conduit inlet having a first expanded cross-section and a second expanded cross-section, the first and second cross-sections being sufficient to create an exothermic catalytic reaction channel having an exit, the exothermic catalytic reaction channel defined by the interior surface of said casing and the conduits exterior surfaces, the first expanded cross-sections connected to one another creating a bundle the bundle connected to said casing, and the exothermic catalytic reaction channel exit and the conduit outlets proximately located such that a first fluid upon exiting the conduit outlet is in contact with a second fluid that has exited the exothermic catalytic channel; and  
       an oxidation catalyst deposited within the exothermic catalytic reaction channel on at least a portion of at least one of the conduit exterior surfaces, the oxidation catalyst being backside cooled from the conduit interior surface by the second fluid.  
     
     
       13. The catalytic firebox reactor of claim  12  wherein the first expanded cross-section is similar to and greater than the nominal conduit cross-section. 
     
     
       14. The catalytic firebox reactor of claim  13  wherein the second expanded cross-section is similar to and greater than the nominal conduit cross-section. 
     
     
       15. A catalytic firebox reactor comprising: 
       a casing having an inlet and an outlet and defining an interior chamber;  
       an inlet retainer having an upstream face and a downstream face, the inlet retainer connected to said casing within the casing inlet;  
       an outlet retainer having an upstream face and a downstream face, the outlet retainer connected to said casing within the casing outlet;  
       at least two conduits, each conduit having an inlet and an outlet and an interior surface and an exterior surface, the conduits positioned longitudinally within the interior chamber, the conduits extending through the inlet retainer and the outlet retainer, the conduits positioned by the inlet retainer and the outlet retainer, the conduit exterior surfaces and the casing interior surface forming an exothermic catalytic reaction channel having an exit, the exothermic catalytic reaction channel exit and the conduit outlets proximately located such that a first fluid upon exiting the conduit outlet is in contact with a second fluid that has exited the exothermic catalytic channel; and  
       an oxidation catalyst deposited within the exothermic catalytic reaction channel on at least a portion of at least one of the conduit exterior surfaces.  
     
     
       16. A catalytic firebox reactor of claim  15  wherein the conduits are connected to the inlet retainer. 
     
     
       17. A catalytic firebox reactor of claim  15  wherein the conduits have a first expansion on the upstream side of the inlet retainer and a second expansion of the downstream side of the outlet retainer, said first and second expansion sufficient enough to prevent passage of the conduit through the retainer whereby the conduits are retained between the inlet retainer and the outlet retainer without fastening. 
     
     
       18. A catalytic firebox reactor comprising: 
       a casing having an inlet and an outlet and defining an interior chamber;  
       at least two conduits having an inlet and an outlet and an interior surface and an exterior surface, the conduits positioned longitudinally within the interior chamber;  
       a support plate being open to the passage of fluid positioned within said casing inlet connected to said casing, the conduits passing through the support plate and connected thereto within the interior chamber, the conduit exterior surfaces and the casing interior surface forming an exothermic catalytic reaction channel having an exit, the exothermic catalytic reaction channel exit and the conduit outlets proximately located such that a first fluid upon exiting the conduit outlet is in contact with a second fluid that has exited the exothermic catalytic channel; and  
       an oxidation catalyst deposited within the exothermic catalytic reaction channel on at least a portion of at least one of the conduit exterior surfaces.  
     
     
       19. A method for creating a more reactive fuel/oxidant mixture, said method comprising: 
       generating a fuel/oxidant mixture;  
       passing a second portion of the fuel/oxidant mixture into cooling channels of a catalytic reactor;  
       simultaneously passing a first portion of the fuel/oxidant mixture into the catalytic reactor at an entrance velocity greater than the flame propagation velocity and into contact with exothermic reaction surfaces, the surfaces being in a backside cooled relationship with the cooling channels;  
       reducing the velocity of the first portion while in the catalytic reactor; and  
       mixing the first portion and the second portion after exiting the catalytic reactor.  
     
     
       20. The method of claim  19  further comprising the step of increasing the velocity of the second portion while in the cooling channels. 
     
     
       21. A method for creating a more reactive fuel/oxidant mixture, said method comprising: 
       passing a first fuel/oxidant mixture into a single exothermic catalytic reaction channel of a catalytic reactor, the exothermic catalytic reaction channel having an oxidation catalyst deposited therein;  
       simultaneously passing a second fuel/oxidant mixture into the cooling conduits of the catalytic reactor, the conduits passing through the exothermic catalytic reaction channel; and  
       combining the cooling conduit effluent and reaction channel effluent.  
     
     
       22. The method of claim  21  wherein said first fuel/oxidant mixture and said second fuel/oxidant mixture are from the same source, and the first step of the method is splitting a fuel/oxidant mixture into a first and second fuel/oxidant mixture.